题干
I really don’t know____I had my walet stolen.
A：when it was that
B：that it was whe
C：where was it that
D：it was where that
答案(点此获取答案解析）
A
A：when it was that
B：that it was whe
C：where was it that
D：it was where that
的前
项和为
，若
，
，则
